Preparation of sustainable of eco-friendly MWCNT-geopolymer composites with superior sulfate resistance

The main purpose of the paper is to prepare and characterize sustainable geopolymer composites with high potential to resist sulfate attack. The produced eco-friendly composites were produced from metakaolin as well blast furnace slag incorporating 10% of either silica fumes or glass waste powder as control mixes. multiwall carbon nanotube (MWCNT) was added from 0.01 up to 0.09% by weight. Addition of MWCNT results in an increased sulfate resistance up to 0.07% for both matrices incorporating glass waste or silica fume. This encourages the sustainability of the produced composites in marine environments. However, glass waste mixes exhibited greater stability and high mechanical properties than silica fume mixes as related to difference in their reactivity. Differential thermal gravimetric, FTIR, and XRD of hardened geopolymer composites with carbon nanotube of 0.01 up to 0.09 wt% depicted an increased amorphous geopolymer as well as hydrating phases with little evidence of ettringite formation up to 0.07%.